290 



SUMMARY OF CURRENT RESEARCHES RELATING TO 



FiG 



moves over the stage, so that the complete immobility of the object is 

 assured. "If one reflects on the necessity of attaching indiarubbcr 



tubes to two glass tubulures, and to 

 be certain of the perfect immobility 

 of certain anatomical elements, the 

 advantage of such an arrangement 

 will be readily understood. Ex- 

 periments in the culture of ferments, 

 the absorption of gases, the rarefac- 

 tion and compression of air are 

 thus greatly facilitated." * 



The most complete form of 

 apparatus, however, for experi- 

 menting with gases is the Strieker- 

 Sanderson hot stage, which is described and figured in this Journal, 

 1887, p. 309, fig. G8. 



To allow of a rapid change of gases, Lancaster s apparatus! (fig. 52), 

 made out of a watch-glass, had two glass tubes for the entrance of the 



Fig. 52. 



gases. These were connected with indiarubber tubes provided with 

 spring clips, so that different gases could be experimented with in rapid 

 succession. 



Fis. 53. 



Hansen's Moist Chamber £ is shown in fig. 53, where A is a glass 

 plate with a central aperture F, and having two rings C and B. The 



* Catalogue, 1886 pp. 33-5 (2 figs.). t Dippel, op. cit., p. 661 (1 fig.). 



X Meddelelser fra Carlsberg Laboratories 1881, pp. 184-6 (2 figs.), with French 

 resume. 



